Newsletter No 1 March 2011

The lesson of Easter Island

Jan J. Boersema

In my book, Beelden van Paaseiland Over de duurzaamheid van een cultuur (Statues of Easter Island On the sustainability of a culture), to be published by Atlas in mid-April, I reconstruct the ecological and cultural history of this fascinating island. In doing so, I dispute the commonly-held views of the kind found in environmental science literature.

Easter Island was given its name by Jacob Roggeveen. A native of Zeeland in the Netherlands, he was the first European to set eyes on the island, on Easter Day, 1722. He wondered how the island had come to be inhabited. It is the world’s most isolated populated location, and the question of how the Polynesians ever managed to reach it is shrouded in mystery. They built up a thriving statue culture and it is these statues – the moai – that have become the island's icons, towering several metres high. But the island itself has also become an icon for environmental scientists. It is said that a premodern collapse occurred as a result of the overexploitation of the natural environment. This hypothesis owes its pre-eminence primarily on account of the books by Clive Ponting (A Green History of the World, 1991) and Jared Diamond (Collapse: How Societies Choose to Fail or Survive, 2005) and can be found in many a textbook on environmental science. The story of Easter Island is seen in this context as historic ‘proof’ of the Club of Rome model. The catastrophe of which the Club of Rome warns us is said to have already taken place – on Easter Island.

The heart of the collapse hypothesis concerns the effects on nature of the overexploitation of natural resources, and on the culture that depends on that same nature. The most prominent feature of the collapse is the sudden decline in population numbers. At issue on Easter Island was the overexploitation of the original woodland. When the first inhabitants arrived, three-quarters of the island was covered by trees. In around 1550, there was no longer sufficient wood for making seaworthy canoes, and it also became impossible to move the moai from the quarries to their intended location. The deforestation is said to have led to erosion, causing fertile soil to be washed away, which meant that not enough food could be produced. According to Ponting, Diamond and others, the result was starvation and conflict in the face of increasingly scarce resources. This eventually degenerated into war and cannibalism, a loss of social structures and a severely decimated population. When Roggeveen set foot on the island in 1722, he encountered the woeful remnants of a once fine culture.

This is an appealing version of events, but in my book I make clear that it cannot have happened this way. Roggeveen, in fact, described the island and its inhabitants in very positive terms. The Dutch exchanged linen for bananas and chickens, and noted that the vegetable plots were very neatly organized. The historic shipping journals of the day do not tally with the picture outlined by Ponting and Diamond – it is likely that they did not read these particular sources or at least, only cursorily. More recent research also fails to support the collapse theory.

Although the process of deforestation did occur, it has not been demonstrated that this jeopardized food production. The islanders were well able to deal with the risk of desiccation of the fields and vegetable plots: where necessary, they applied mulch. This was an agricultural concept that they had developed at an early stage, in the fourteenth century. All the written sources from the eighteenth and nineteenth centuries confirm the picture of a level of food production that was more than adequate. Visitors to the islands never saw people in a state of starvation. Trading activities were conducted with every passing ship, with food from Easter Island featuring in the transactions. Even if just a small part of the island were to be cultivated and work performed only a few days a year, there would still be enough, wrote visitors and missionaries. So if there had been a period of serious starvation before the arrival of the Dutch, then this would not necessarily have been a consequence of the soil being impoverished, eroded and exposed through deforestation. The idea that soil in that condition would be able to recover in just a few decades to the levels of fertility witnessed by European visitors is out of the question.

Large-scale starvation and mortality can be detected paleopathologically – from bones discovered at the scene, in other words. That applies even more strongly in the case of death resulting from violence and conflict. Any search for evidence to back up this particular aspect of the hypothesis too will prove fruitless: no indication of this has been found for the period concerned, between 1550 and, at the latest, 1750. There are some signs that people suffered from stress and it is probable that there were those on Easter Island who met a violent end, as they do anywhere else. However, it is difficult to pass this off as proof of societal collapse. The expert in this area, George Gill, has therefore concluded from his evaluations of his own work and that of others, that the inhabitants of Easter Island were generally healthy in the period preceding contact with outside visitors. This is in line with research carried out by Caroline Polet, who has examined the teeth in the skulls of the islanders dating from between the seventeenth and the nineteenth centuries. From the shape and chemical composition of the teeth, it is possible to derive a picture of the health of the owner. She found evidence of stress, especially among young girls, but the general state of health was better than that on other Polynesian islands and in Europe at the time.

What, then, is there left to say about the decline of the population? I make clear in my book that the maximum number of inhabitants can never have exceeded 10,000, and was probably much lower. I have also calculated that even if there were 10,000 people on the island, it would still have been possible to produce enough food.

Based on these and other arguments, I believe that the society underwent a gradual change as circumstances evolved. It was not the sustainability of the culture that was at issue, but the quality. They managed to survive very well in an impoverished natural environment – in a cultural and religious sense, too. The cult of statues was replaced by the birdman cult.

I advise anyone who is interested in the whole story and the fascinating details, anyone who would like to read about the collapse that took place on the island but which had nothing to do with natural resources, and anyone who is eager to learn about the lessons that I have drawn for the present debate on a sustainable world, to read this book.